Surgical dressing



y 3 6 L. G. szUcs 3,322,119-

SURGICAL DRESSING Filed Dec. 17, 1962 Fig. 4

ulhm Mr United States Patent M 3,322,119 SURGICAL DRESSING Laszlo G. Sziics, 6 Ackermannstrasse, Zurich, Switzerland Filed Dec. 17, 1962, Ser. No. 245,098 Claims priority, application Switzerland, Dec. 18, 1961, 14,683/61 7 Claims. (Cl. 128156) This invention relates to a surgical bandage or dressing.

The human organism has the tendency to close up a wound as fast as possible, either by forming a scurf or by covering it with epithelium. It is a very important prerequisite for this complex process of wound healing to leave the wound undisturbed. On the occasion of a change of the dressing, the phenomena of resorptio and remotio should be substantially free of outside influences, so that the cooperation of the body with the wound-healing is not disturbed.

It is surgical practice to remove a bandage to be changed by a single, fast tearing movement so that the patient only perceives the sensation of a short pain. Therefore the granulation tissue is frequently disturbed in those areas where the bandage tenaciously adheres to the Wound, with dried blood forming an integral mass with the bandage. In these areas the epithelization is disturbed and the scurf formation might be such that a scarred tissue forms later It had already been proposed to reduce the adhesion of wound bandages by the application of non-absorbent but liquid-permeable dressings with a smooth surface, e.g. perforated plastic foil. Nevertheless these dressings are not fully satisfactory. The usual band-aids generally consist of a dense fabric with low stretchability whereas the adhesive represents a film of a relatively high stretchability. Such a bandage can be removed with a single quick pull. Since the adhesive power of the usually elastic adhesive agent should not fall below a certain value to avoid an undesirable yielding or loosening of the bandage, it is generally necessary to exert a rather strong pull to separate the bandage from the skin. This procedure is therefore not only painful for the patient, but also may cause injury to the granulation tissue on the healing wound.

It is an object of the invention to provide a surgical dressing which avoids the mentioned difficulties. According to the invention, the dressing and/or a portion of the bandage which adheres on the skin comprises a porous fibrous thread structure, in which at least those threads which run in one direction are highly stretchable or extensible. A dressing consisting of this thread structure absorbs at least a portion of the blood which coagulates and hardens. When the threads are stretched in order to loosen the bandage, the blood particles which are contained in the thread structure and which cause the adhesion of the structure to the wound are sheared off, so that the bandage is separated from the wound without disturbing the same. An analogous effect occurs with the band-aid, the elastic thread structure of which is penetrated by the adhesive which adheres to the skin. When an adhesive is used the stretchability of which, as measured by its ultimate linear elongation, is lower than that of the threads, the adhesive particles which are contained in the thread structure and which bond the same to the skin are sheared off after this thread structure is sutficiently stretched to pull the bandage off the skin, so that also in this case the bandage is removed from the skin without tearing.

The accompanying drawings show examples of the wound bandage of this invention.

FIGURE 1 represents an example of a surgical dressing in perspective view,

FIGURE 2 is a diagrammatic view of a second example of a surgical dressing,

3-,3ZZ,1 19 Patented May 30, 1967 FIGURES 3 and 4 show two further modifications of a dressing,

FIGURE 5 is a cross-sectional view of an applied dress- 1ng.

Referring now to FIGURE 1, the represented dressing comprises two lateral portions 10 and 11, which are coated with adhesive. The center portion 12 which forms the wound contacting area is provided with an absorbing pad 13 which is covered with a fabric made of stretch yarn.

Portions 10 and 11 consist of parallel threads which are bonded together by adhesive only. The stretchability of the threads is much higher than that of the adhesive, so that upon a certain stretch applied to the thread structure, the adhesive layer becomes torn apart. When the dressing is pulled off the skin, the stretchable threads become extended and thereby are prevented from receiving much of the tension applied, while most of the latter is transmitted to the adhesive. The adhesive film however, can not sustain this tension due to its low strength so that it becomes disrupted immediately. Therefore the thread structure separates from the adhesive and is easily removed from the skin. The torn adhesive film is then removed from the skin without difiiculty.

Preferably the portion of the thread structure which carries the adhesive consists of a non-woven layer of parallel threads bonded together by the adhesive. When such a bandage is pulled olf the skin, the adhesive film becomes disrupted and the portion of the bandage which is supported merely by the parallel threads disintegrates. It is preferred to use stretch yarn. In this case the dressing, which as a whole consists of a fabric, is formed only of warp threads in the adhesive bearing portions. A longitudinal pull on this flexible warp threads unavoidably results in rupturing the adhesive film, so that the thread structure disintegrates and the dressing can be removed.

In another embodiment of the invention the whole dressing consists of a fabric woven from threads, the extensibility of which is higher than that of the adhesive. Also in this case a stretch yarn or another extensible yarn can be used.

A dressing having a cover sheet of thin plastic foil can also be arranged in the described manner. In this case an adhesive can be used, on one hand, for bonding the cover sheet to the thread structure and, on the other hand, for attaching the latter to the skin. In order to remove the dressing from the skin, the plastic foil is slightly detached from the underlying parts of the dressing along an edge so as to make the thread structure accessible and the latter is pulled, so that the adhesive between the thread structure, the skin and the cover sheet becomes disrupted owing to pulling and shearing effect and the dressing can be easily removed.

When removing the described dressing from a wound, it is not necessary as it was the case heretofore, to pull off the skin a relatively ductile, tenacious film of adhesive maintained by a barely extensible fabric, because the thread structure, owing to its yielding extensibility, does not offer any support to the adhesive, so that the film of adhesive practically is immediately ruptured, without transmitting any pulling action upon the skin. It therefore suffices to render the threads in the structure more extensible than the adhesive film. The intrinsic ultimate extensibility of a thin plastic film is always smaller than the adhesion of the adhesive to the skin, so that the film becomes disrupted before the full force necessary to remove the adhesive from the skin becomes effective on the latter. The disrupting of the adhesive film however ensures the separation of the bond between the adhesive film and the thread structure so that the latter can be removed without difiiculty.

The removal of the described dressing is practically painless and does not disturb the healing of the wound. Also the mobility of the skin underneath the dressing is maintained as the thread structure only possesses little stiff- 3 ness and the movements of the skin are taken up exclusively by the adhesive.

Preferably, the dressing is of rectangular shape and will be provided with adhesive at least on two opposite marginal areas, whereas the center section either includes a portion to be applied on the wound or will bear upon such a portion when the dressing is applied. Preferably this center section is formed as an absorbing layer of relatively high extensibility. When removing the dressing, the center section is stretched, whereby the hard, brittle blood mass inside disintegrates by shearing action; accordingly, even a dressing sticking to the wound can be removed without pain and without injuring the regenerated tissue.

The described dressing may also have adhesive carrying marginal portions like and 11 on all four sides. In this case the dressing preferably consists of two separate superposed layers. The lower layer, functioning as an absorbing wound dressing, is an extensible thread structure with two opposite marginal portions which consist of parallel threads bonded together by and carrying the adhesive. The upper layer is a thread structure having also two adhesive carrying marginal portions and extending crosswise of the first layer. When the bandage is changed, both layers are pulled off consecutively.

In a practical embodiment of my invention, the thread structure is made of so called stretch yarn, this being the trade term for a yarn consisting of one or more highly crimped or curled, preferably continuous synthetic fiber filaments, which due to this crimped or curled configuration is easily stretchable. The adhesive applied to the thread structure e.g. by a brush roll, consists of 50 parts Lutonal 360 D (dispersion of 55% polyvinyl ether) and 75 parts of distilled water. The fabric of this dressing offers the further advantage to be air-permeable, which enables the skin to breathe underneath the dressing, thus avoiding the possibility of eczema formation. When for instance the wound dressing of elastic, porous fabric, as shown in FIG- URE 5, is pulled in the direction of the arrow A, the extensible, e.g. stretch yarn is stretched, the dried blood inside of the threads 15 forming the solid bond between the absorbing wound dressing and the wound 21, is ruptured in the direction of the arrow and the fabric can be removed from the wound 21.

In FIGURE 2 the weft threads 14 are formed by stretch yarn, and the warp threads 15 of the center portion 12 to be applied upon the wound, are also of stretch yarn.

FIGURE 3 shows the application of stretch yarn only for the warp threads 16 of the marginal portions 10 and 11.

In FIGURE 4 the warp threads 17 of the center portion 12 are formed by stretch yarn, while the marginal portions 10 and 11 are formed by single threads 18 which are parallel in weft direction.

In a preferred embodiment stretch yarn made from nozzle-spun synthetic fibers or filaments is used for producing the thread structure. Such fibers have an absolutely smooth surface and are nearly non-absorbent, so that they will adhere but little to the Wound. However, stretch yarns 7 produced from other fibers can be used as well for the puron the two opposite sides of the dressing before he re- 6 moves the latter from the wound. This pull extends the stretch fibers, to approximately their double length so that the dry blood in the interstices or loops of the dressing, strongly bonding the absorbing fabric to the wound, is ruptured and the fabric is separated from the wound. Thus the surgeon may remove the bandage without pain and without injuring the granulation tissue. Therefore the wound is not disturbed, scab is not formed and a smooth epithelization is guaranteed.

The dressing may be treated with an ointment base. In this case the curls or ripples of the stretch yarn offer the advantage to incorporate larger amounts of ointment base in their loop formation than would be possible, if straight threads were used.

I claim:

1. A surgical dressing comprising a portion to be applied to a wound and portions adapted to adhere to the skin surrounding said wound, said portions adapted to adhere to the skin consisting of yarn threads and of a film of adhesive material bonding said yarn threads to each other, at least part of said yarn threads being stretchable whereby said thread structure is extensible in at least one direction, the extensibility of said yarn threads as measured by their ultimate elongation being greater than that of said film of adhesive material whereby the latter is adapted to become disintegrated by application of a pull to said thread structure in said at least one direction.

2. A surgical dressing according to claim 1, in which the adhesive carrying portion of the thread structure comprises parallel stretchable threads bonded together by the adhesive.

3. The surgical dressing of claim 1, in which the adhesive carrying portion of the thread structure is an extensible fabric.

4. The surgical dressing of claim 1, in which the said stretchable yarn threads of the adhesive carrying portion of the thread structure consist ofextensible stretch yarn.

5. The surgical dressing of claim 1, in which the unexpanded thread structure is bonded to an integral adhesive film.

6. The surgical dressing of claim 1, in which the adhesive penetrating the unextended thread structure forms an adhesive film on one sideof the structure and causes a cover sheet to adhere to the other side of the structure.

7. The surgical dressing of claim 1, comprising two separate superposed thread structure layers each having two opposite adhesive carrying marginal portions assembled crosswise of each other.

7 References Cited UNITED STATES PATENTS 1,748,470 2/1930 Domizlafi 128-156 2,321,363 6/1943 Crowley 128l56 2,764,976 10/1956 Skiles et al 128156 2,785,677 3/1957 Stumpf 128156 2,810,184 10/1957 Sherman 139-421 2,823,444 2/1958 Davies et a1 l28l56 X 3,033,201 5/1962 Olsen 128-456 3,113,568 12/1963 Robins l28156 FOREIGN PATENTS 241,664 2/ 1961 Australia.

548,949 10/ 1942 Great Britain.

73 8,722 10/ 1955 Great Britain.

5 RICHARD A. GAUDET, Primary Examiner.

ROBERT E. MORGAN, Examiner.

C. F. ROSENBAUM, Assistant Examiner. 

1. A SURGICAL DRESSING COMPRISING A PORTION TO BE APPLIED TO A WOUND AND PORTIONS ADAPTED TO ADHERE TO THE SKIN SURROUNDING SAID WOUND, SAID PORTIONS ADAPTED TO ADHERE TO THE SKIN CONSISTING OF YARN THREADS AND OF A FILM TO ADHESIVE MATERIAL BONDING SAID YARN THREADS TO EACH OTHER, AT LEAST PART OF SAID YARN THREADS BEING STRETCHABLE WHEREBY SAID THREAD STRUCTURE IS EXTENSIBLE IN AT LEAST ONE DIRECTION, THE EXTENSIBILITY OF SAID YARN THREADS AS 